The present invention relates a child seat device to be installed on a seat of a car, and more preferably, to a child seat device including a base fixed to a car-side member and a child seat body mounted on the base.
While conventional child seats are held so as to be fastened on a seat cushion of a car by a webbing of an adult seat belt device, they are inconvenient such that, for example, it is difficult to know how to pass the webbing.
Accordingly, Japanese Patent Publication (KOKAI) No. 2000-280800 proposes a child seat device in which car-side members only for fixing the child seat device are placed on right and left rear sides of a seat, a base is connected to the car-side members, and a child seat body is mounted on the base.
FIG. 9 is a perspective view showing a configuration of the child seat device.
The child seat device comprises a child seat body 12 including a seat portion 30, a back portion 32 and arm portions 34, and a base 18 to which the child seat body 12 is fixed detachably. A connecting bottom plate 14 is combined with the child seat body 12. The base 18 is fixedly placed on a seat cushion of a seat of a car.
The bottom plate 14 comprises a rectangular main plate portion 40, a flange 42 extending from a rear side of the main plate portion 40, an opening 44 formed at the front of the main plate portion 40, and a bar 46 extending parallel to a front side of the main plate portion 40 so as to cross the opening 44.
The base 18 comprises a base body 50 shaped like a rectangular plate, a pair of arms 52 extending rearwardly from right and left rear ends of the base body 50, grip portions 54 formed at leading ends of the arms 52, a hook 56 formed at the front of the base body 50, a bar-engaging member 58, an operating piece 60 for disengaging the hook 56, a swing stopper 62 formed on an upper rear surface of the base body 50 and serving as a swing-preventing member, a lever 64 for releasing the swing stopper 62, a flange-pressing member 66 to be engaged with the flange 42, an operating piece 68 for unclamping the grip portions 54, windows 70 for indicating the gripping condition by the grip portions 54, and the like.
The arm 52 has, at the rear end, the grip portion 54 for gripping one of clamp bars 74 formed on the right and left rear sides of the car seat. The clamp bar 74 extends in the widthwise direction of the car. Each grip portion 54 receives the clamp bar 74 in a recess 76 formed at the rear end of the arm 52, and latches the clamp bar 74 by a hook (not shown) formed inside the recess 76, thereby gripping the clamp bar 74.
In order to unlatch the bar 74 from the hook, the operating piece 68 and the hook are connected via sliding plates 92 and hook-operating rods 94.
The operating piece 68 is movable to the front and rear sides of the base 18 inside an opening 96 formed on the upper surface of the base 18. The sliding plate 92 formed integrally with the operating piece 68 extends rightward and leftward, and is connected to front ends of the hook-operating rods 94. Rear ends of the hook-operating rods 94 are drivingly connected to ends of the hooks. When the rods 94 are moved to the right in FIG. 9, the hooks and the clamp bars 74 are disengaged from each other.
When the right and left arms 52 are connected to the corresponding clamp bars 74, the base 18 can not move to the front, rear, right, and left sides of the car, but the leading end thereof can swing up and down. In order to prevent the leading end of the base 18 from swinging, the swing stopper 62 is provided as a swing-preventing member.
The swing stopper 62 is formed of an inverse-U-shaped pipe. Bottom ends of the swing stopper 62 are connected to and combined with a shaft 100 by pins (not shown). The shaft 100 extends in the right and left directions of the base 18, and is rotatably supported on right and left wall portions 102 of the flange-pressing member 66.
In a normal state, the swing stopper 62 is prevented by a lock mechanism (not shown) from pivoting forward, and is allowed to pivot only rearward. By pushing the lever 64 down, the lock mechanism is released, and the swing stopper 62 is allowed to pivot forward. Therefore, by pressing the swing stopper 62 rearwardly against a seat back of the car seat after the base 18 is placed on the seat and the arms 52 of the base 18 are connected to the clamp bars 74, the base 18 is fixed so that it can not move forward, rearward, rightward, leftward, upward, and downward. The base 18 can be detached from the seat by pivoting the swing stopper 62 forward while pressing the lever 64, and pulling the operating piece 68 forward to release the clamp bars 74 from the grip portions 54.
In order to mount the child seat body 12 on the base 18 fixed on the seat of the car, the flange 42 of the connecting bottom plate 14 is inserted beneath the flange-pressing member 66, the front side of the child seat body 12 is pushed down, and the bar 46 is pushed into the bar-engaging member 58 and is retained by the hook 56, whereby the child seat body 12 is connected to the base 18.
When the bar 46 of the connecting bottom plate 14 is pressed against the hook 56 from above, the hook 56 retracts, and the bar 46 enters a groove of the bar-engaging member 58. When the bar 46 has been completely placed in the groove, the hook 56 advances and covers the bar 46, so that the connecting bottom plate 14 and the child seat body 12 combined therewith are fixed onto the base 18.
In order to release the fixing condition, the hook 56 is retracted by pressing the operating piece 60, and the child seat body 12 can be pulled up.
In this way, the child seat body 12 and the base 18 are separated in the child seat device, and therefore, they can be separately carried into the car and can be separately installed. When fixing the base 18, since the child seat body 12 is separated therefrom, the grip portions 54 of the arms 52 and the clamp bars 74 can be connected easily.
In order to fix the base 18, it is only necessary to engage the arms 52 and the clamp bars 74 and then to tilt the swing stopper 62 rearwardly. This is quite easy, and the fixing strength of the base 18 is remarkably high. In order to fix the child seat body 12 to the base 18, it is also only necessary to insert the flange 42 beneath the flange-pressing member 66 and to then push the front side of the child seat body 12 downwardly. This is quite easy. Moreover, the child seat body 12 and the base 18 are connected quite firmly.
When the car is involved in a head-on collision (including offset collision, this is also applied to the following) during driving, and an impact large enough to stop the car is applied thereto, a quite large forward force acts on the child seat device installed on the seat cushion of the car.
In this case, when the rear bottom of the child seat device is connected to the car-side member and the child seat device is restrained from moving forward, a pivoting force on the car-side member on the rear side is formed in the base. When the pivoting force is quite large, the base pivots on the car-side member, and the front of the base sinks into the seat cushion. With this, a force is applied to the child seat body fixed on the base so that the front thereof sinks.
An object of the present invention is to provide a child seat device which reduces such downward movement of the front of a child seat body caused in the case of a head-on collision of the car.
A first aspect of the invention provides a child seat device having a base placed on a seat cushion and connected at the rear thereof to a car-side member, and a child seat body placed on the base. The child seat device includes a guide member extending forward and upward from the front of the base, and an engaging member which engages with and moves along the guide member.
In such a child seat device according to the first aspect of the invention, the front of the child seat body is connected to the base, which is placed on the seat cushion of the car seat and is connected to the car-side member at the rear thereof, via the engaging member and the guide member engaging the engaging member. In this case, since the engaging member is movable along the guide member, the front of the child seat body can move relative to the base in the forward and upward directions which correspond to the extending direction of the guide member.
Accordingly, even when the base of the child seat device pivots, and the front thereof sinks into the seat cushion in the case of a head-on collision during driving, the front of the child seat body is separated from the base and swings forward and upward along the guide member. Therefore, the child seat body will not incline forward while following the pivotal movement of the base, and a heavy load will not be imposed on the passenger sitting in the child seat body.
According to a second aspect of the invention, in the child seat device, preferably, the engaging member disposed at the front bottom of the child seat body is a bar extending in the widthwise direction of the child seat body, and the guide member includes a first guide portion rising forward and upward from the base, and a second guide portion extending nearly parallel to the first guide portion along the rear side of the first guide portion. The top of the second guide portion is connected to the first guide portion, and the bottom of the second guide portion is spaced from the base. Thus, a space is formed between the bottom of the second guide portion and the base so as to allow the bar to move therein.
This structure makes it easy to connect the child seat body and the base and to detach the child seat body from the base.
Namely, in order to connect the child seat body to the base, it is only necessary to pass the bar formed at the front bottom of the child seat body between the first guide portion and the second guide portion from below the second guide portion which is spaced from the base. In order to detach the child seat body from the base, it is only necessary to draw the bar from between the first guide portion and the second guide portion through the space formed beneath the second guide portion which is spaced from the base. In a state in which the child seat body and the base are connected, that is, in a state in which the bar serving as the engaging member is engaged with the guide member, of course, since the bar extending in the widthwise direction of the child seat body is movable between the first guide portion and the second guide portion, the front of the child seat body can move in the forward and upward direction corresponding to the extending direction of the guide member.
In the child seat device according to the second aspect of the invention, an energy-absorbing member may be formed between the first guide portion and the second guide portion so as to deform and absorb the kinetic energy of the child seat body when the bar moves between the first guide portion and the second guide portion (third aspect of the invention).
In such a structure, when the child seat body moves forward along the guide member in the case of a collision of the car, as described above, the kinetic energy thereof is absorbed by the energy-absorbing member via the bar. This substantially reduces the load to be applied to the passenger sitting in the child seat body.
Instead of forming the energy-absorbing member in the guide member, the top of the first guide portion and the top of the second guide portion may be elastically connected, and at least one of the opposing faces of the first guide portion and the second guide portion may be provided with a projection which is pressed by the bar so as to move the second guide portion closer to and away from the first guide portion when the bar moves therebetween (fourth aspect of the invention).
In such a structure, since the kinetic energy of the child seat body is absorbed because the bar elastically moves relative to the second guide portion closer to and away from the first guide portion when the bar moves between the first guide portion and the second guide portion, the load to be applied to the passenger sitting in the child seat body in the case of a head-on collision of the car can be substantially reduced, in a manner similar to that of the above-described energy-absorbing member.
A fifth aspect of the invention provides a child seat device having a base fixed on a seat cushion, a child seat body placed on the base, and a connecting member for connecting the rear bottom of the child seat body and the car-side member or the rear of the base, wherein the connecting member increases the length thereof while absorbing the kinetic energy of the child seat body when a tension higher than a predetermined value is applied thereto from the child seat body.
In such a child seat device according to the fifth aspect of the invention, the child seat body is bound on the seat while the connecting member disposed at the rear bottom thereof is connected to the car-side member or the rear of the base. When the car collides at the head, the connecting member increases its length while absorbing the kinetic energy of the child seat body. This substantially reduces the load to be applied to the passenger sitting in the child seat body.